Weathering resistance of thin plasma polymer films on pre-coated steel

O trabalho apresentado teve origem no projecto de investigação “Tailored Thin Plasma Polymers Films for Surface Engineering of Coil Coated Steel”, financiado pelo Programa Europeu ECSC Steel Research. Sistemas de aço galvanizado pré-pintado em banda à base de poliéster e poliuretano foram submetidos a um processo de polimerização por plasma onde um filme fino foi depositado de modo a modificar as propriedades de superfície. Foram usados reactores de cátodo oco, microondas e rádio frequência para a deposição do polímero fino. Os sistemas preparados foram analisados de modo a verificar a influência do processo de polimerização por plasma na alteração das propriedades barreira dos sistemas pré-pintados em banda. Foi estudado o efeito dos diferentes passos do processo de polimerização por plasma, bem como o efeito de diferentes variáveis operatórias. A mistura precursora foi variada de modo a modificar as propriedades da superfície de modo a poder vir a obter maior hidrofobicidade, maior resistência a marcas digitais, bem como maior facilidade de limpeza. Os testes foram conduzidos em solução de NaCl 0,5 M. Para o trabalho foram usadas técnicas de análise da morfologia da superfície como Microscopia de Força Atómica e Microscopia Electrónica de Varrimento. As propriedades electroquímicas dos sistemas foram estudadas por Espectroscopia de Impedância Electroquímica. A estrutura dos filmes gerados no processo de polimerização por plasma foi caracterizada por Microscopia de Transmissão Electrónica. A modificação das propriedades ópticas devido ao processo de polimerização por plasma foi também obtida.

Correlação entre argamassas e betões com base em análise reométrica

O presente trabalho teve como objetivo principal estudar a correlação no estado fresco e no estado endurecido entre argamassas e betões com pozolanas, nomeadamente, um metacaulino e uma diatomite. Este trabalho procurou também otimizar a utilização dos materiais pozolânicos na produção de argamassas e betões. O estudo do comportamento reológico inicia-se com a avaliação da argamassa padrão e do betão padrão, utilizando para tal reómetros adequados a cada material. O comportamento reológico das argamassas com pozolanas foi analisado em função do comportamento da argamassa padrão. Verificou-se que é possível ajustar o comportamento reológico de argamassas com pozolanas ao comportamento da argamassa padrão e, deste modo, obter-se também betões correspondentes (com pozolanas) dentro do intervalo de trabalhabilidade pretendido e pré-definido para o betão padrão. Também foi possível concluir que, até um determinado teor de material pozolânico, se verificava uma correlação entre os parâmetros reológicos (viscosidade e tensão de cedência) das argamassas e os seus betões correspondentes. Na caracterização das argamassas e betões no estado endurecido, verificou-se a existência de uma correlação entre a resistência à compressão das argamassas e as resistências dos betões correspondentes para a maioria das formulações. Quando o ajuste de trabalhabilidade foi efetuado através da alteração do teor de água, apenas as formulações com metacaulino apresentavam uma relação linear entre as resistências das argamassas e a dos betões correspondentes. Usando um agente redutor de água de amassadura para o ajuste de trabalhabilidade, as formulações com metacaulino continuam a apresentar uma relação linear entre as resistências das argamassas e as resistências dos betões. As formulações mistas, com metacaulino e diatomite, também apresentam uma relação linear entre o valor das resistências das argamassas e dos betões. As composições com diatomite não mostram esta relação linear entre a resistência das argamassas e a resistência dos betões, embora exista uma correlação entre elas. O estudo de algumas propriedades no estado endurecido de betões mostrou que a utilização de água como elemento de ajuste de trabalhabilidade diminui sempre a resistência à compressão dos betões com o aumento do teor em pozolana. O uso de um agente redutor de água de amassadura, principalmente no caso da utilização do metacaulino, aumenta a resistência dos betões face ao padrão devido à sua maior reatividade pozolânica relativamente à diatomite. Estas tendências para os resultados observados na resistência mecânica foram também visíveis no módulo de elasticidade e justificáveis pela evolução da microestrutura avaliada conjuntamente por porosimetria, análises térmicas e microscopia eletrónica de varrimento. Finalmente, no estudo da influência dos materiais pozolânicos sobre a durabilidade dos betões, especificamente sobre a resistência à penetração de cloretos, ambas as pozolanas mostraram um efeito bloqueador à penetração de cloretos e, também aqui esse efeito foi mais evidente em composições com metacaulino e na presença de um agente redutor de água de amassadura.

Formação de professores e atividades práticas de astronomia no 1º CEB

Os estudos sobre astronomia e educação em astronomia com professores em serviço são escassos e o seu aumento significativo, nos últimos anos, denota a importância desta área na literacia científica dos cidadãos. Há uma necessidade de divulgar esse conhecimento para superar algumas dificuldades, tais como, a prevalência de conceções alternativas e a falta de implementação de atividades práticas no 1º Ciclo do Ensino Básico. Neste contexto, foi implementado um estudo quasi-experimental com professores e alunos dos 3º e 4º anos de escolaridade de escolas da costa norte de Portugal, que integrou aplicação de questionários diagnósticos em mais de um momento, e uma ação de formação sobre astronomia, para professores. A intenção era verificar se as conceções em relação à astronomia, de professores e alunos, estavam em conformidade com as descritas na literatura, e se a ação de formação, com base em atividades práticas, concebidas com materiais acessíveis e adequadas para colocar em prática com os alunos, foi resposta para melhorar os seus conhecimentos científicos e a prática docente. A análise dos dados a partir do pré-teste revelou conceções alternativas de acordo com a literatura. Os resultados verificados no pós-teste, administrado um ano mais tarde, para o grupo experimental de professores, e comparados com os do grupo de controlo, mostraram que a totalidade dos elementos do grupo experimental evidenciaram uma melhoria significativa no conhecimento científico e uma mudança concetual, devido ao desenvolvimento profissional implementado. Também se verificou que a realização de atividades práticas, através de metodologia de investigação, permitiu que os alunos pudessem compreender como funciona a ciência, o que se traduziu em progresso ao nível das aprendizagens e atitudes. A prática efetiva de atividades hands-on e minds-on parece ser uma maneira apropriada para construir e reforçar o conhecimento científico nesta área, acerca de fenómenos não observáveis. Advoga-se, assim, a importância da formação de professores ao longo da carreira docente como forma de atualizar o processo de ensino e aprendizagem, tendo em vista uma escola capaz de preparar os alunos para uma sociedade cada vez mais exigente e influenciada pela constante mudança no conhecimento proporcionado pelo desenvolvimento científico e tecnológico.

L'agencement des relations père-enfant et mère-enfant : liens avec le développement social d'enfants d'âge préscolaire de familles nucléaires

Ce mémoire s'intéresse à l'agencement des relations qu'un enfant maintient avec ses deux parents et à leurs effets sur le développement social de l'enfant. Plus spécifiquement, ce mémoire explore les relations d'attachement et d'activation. Si le premier terme ferait traditionnellement référence à la relation spécifique entre une mère et son enfant, l'activation concernerait plutôt, selon certains auteurs, la relation entre un père et son enfant. Les psychoéducatrices et psychoéducateurs sont très souvent appelés à soutenir les personnes sur le plan de leur développement social. L'une des fondations cruciales du développement de la socialité serait la première relation créée et maintenue entre un enfant et son premier donneur de soins : la relation d'attachement. En effet, la relation d'attachement, selon la définition classique, référerait davantage à la relation spécifique que les enfants maintiendraient généralement avec leur mère. La façon dont l'enfant entrera ultérieurement en contact avec les personnes de son environnement pourrait être calquée sur cette première relation. Si, au départ, on s'intéressait davantage à l'attachement mère-enfant, plusieurs études ont tenté d'intégrer le père au modèle classique de l'attachement. Il semble que les pères s'intégreraient plus difficilement à ce modèle classique. Certains l'expliquent en faisant valoir que les prémisses théoriques de l'attachement se seraient plutôt concentrées sur la dimension simplement sécuritaire qui serait plus adaptée pour les mères. Les pères auraient un mode d'entrée en relation avec leurs enfants qui serait beaucoup plus dynamique, caractérisé par des jeux physiques chaleureux, mais où les limites seraient clairement définies par l'autorité du parent. Ce type de relation s'appelle la relation d'activation. La relation d'activation favoriserait chez l'enfant la persévérance et l'autorégulation face à l'exploration sécuritaire de son environnement, et par le fait même, constituerait le pendant exploratoire de la relation d'attachement. Des études ont déjà montré les liens de la relation d'activation avec le développement social de l'enfant. Si le cadre théorique de l'activation a été pensé en fonction du père, il reste encore à savoir si la mère peut aussi prendre sa place dans cette relation dynamisante. Alors qu'au Québec, l'organisation des rôles familiaux est en constante évolution, il convient de bien comprendre d'abord les agencements relationnels de la famille nucléaire afin d'éventuellement outiller les parents de familles d'autres types. Pour explorer les mécanismes relationnels, une recension des écrits systématique a été réalisée. L'un des constats les plus intéressants de cette recension est l'absence d'études ayant étudié l'activation et le développement social auprès des enfants de plus de 36 mois. De plus, les deux types de relations (attachement et activation) n'ont pas été vérifiés chez les deux parents d'une famille nucléaire. Un dernier constat concerne enfin les instruments utiliser pour mesurer le construit de la sécurité d'attachement : il semble que, selon l'outil choisi et le type de variable utilisé, les constats réalisés sur la sécurité d'attachement diffèrent. Afin de répondre à cette lacune, le présent projet propose une avenue novatrice, à titre exploratoire : vérifier l'agencement des relations d'activation et d'attachement dans une triade familiale (un enfant et ses deux parents biologiques), et son lien avec le développement social de l'enfant. Étant donné les ressources limitées, seulement cinq cas ont été recrutés. Des données ont été collectées par observation directe et indirecte, selon un devis transversal. Puis les données ont été analysées d'abord de façon descriptive. Quelques analyses corrélationnelles ont toutefois été réalisées à titre exploratoire. Malgré l'impossibilité de généraliser les résultats de cette étude, ces derniers présentent plusieurs points similaires à la littérature scientifique. Le constat le plus évident est le lien entre les problèmes d'activation et les difficultés de comportements internalisés qui ont aussi été documentés dans la littérature scientifique. Ce projet consolide l'intérêt de s'intéresser aux deux dimensions de la relation parent-enfant, tant en recherche que sur le plan de l'évaluation psychosociale de l'enfant.

South Carolina Energy Office pre-approved Energy Efficiency Products and Measures

South Carolina law (48-52-640) requires state agencies to submit a disclaimer statement to the State Energy Office with its annual report stating that it did not purchase an energy conservation product that had not been certified by the State Energy Office. This is a list of preapproved products, retrofits and upgrades.

Hotel Brand Conversions: What Works and What Doesn’t

As many as one-third of U.S. hotels have been converted from one brand to another in recent years, a process that frequently improves the hotel’s financial performance—although that is not always the case. Using data collected between 1994 and 2012 from PKF Hospitality Research, an analysis of brand conversions by 260 hotels shows that hotels moving downscale generally improved their occupancy, and thus their top-line revenue and profit ratios, compared to a control group of 2,750 hotels that did not change brands. However, hotels that moved upscale did not see notable changes in revenue or profit, nor did hotels that moved across their tier, especially when they stayed within their brand family. Two factors seem to drive the financial results for converted hotels—the relative strength of the brand and the fit between the brand and the property.

O papel do lúdico na aprendizagem matemática

Trabalho de projecto de mestrado, Educação (Didáctica da Matemática), Universidade de Lisboa, Instituto de Educação, 2011

Joaquim Rodrigo:a contínua reinvenção da pintura

Tese de doutoramento, História (História da Arte), Universidade de Lisboa, Faculdade de Letras, 2014

The Long Range Transport of Birch (Betula) Pollen from Poland and Germany Causes Significant Pre-season Concentrations in Denmark

Background Birch pollen is highly allergic and has the potential for episodically long range transport. Such episodes will in general occur out of the main pollen season. During that time allergy patients are unprotected and high pollen concentrations will therefore have a full allergenic impact. Objective To show that Denmark obtains significant quantities of birch pollen from Poland or Germany before the local trees start to flower. Methods Simultaneous observations of pollen concentrations and phenology in the potential source area in Poland as well as in Denmark were performed in 2006. The Danish pollen records from 2000-2006 were analysed for possible long range transport episodes and analysed with trajectories in combination with a birch tree source map. Results In 2006 high pollen concentrations were observed in Denmark with bi-hourly concentrations above 500 grains/ m3 before the local trees began to flower. Poland was identified as a source region. The analysis of the historical pollen record from Copenhagen shows significant pre-seasonal pollen episodes almost every year from 2000-2006. In all episodes trajectory analysis identified Germany or Poland as source regions. Conclusion Denmark obtains significant pre-seasonal quantities of birch pollen from either Poland or Germany almost every year. Forecasting of birch pollen quantities relevant to allergy patients must therefore take into account long-range transport. This cannot be based on measured concentrations in Denmark. The most effective way to improve the current Danish pollen forecasts is to extend the current forecasts with atmospheric transport models that take into account pollen emission and transport from countries such as Germany and Poland. Unless long range transport is taken into account pre-seasonal pollen episodes will have a full allergic impact, as the allergy patients in general will be unprotected during that time.

The Summer Concert Band, 5th Festival of Contemporary Works, July 18, 1951

Concert program for The Summer Concert Band, 5th Festival of Contemporary Works, July 18, 1951

O educador de infância em contexto hospitalar

Tese de doutoramento, Educação (Psicologia da Educação), Universidade de Lisboa, Instituto de Educação, 2016

The BBC's role in the changing production ecology of pre-school television in Britain

This paper examines the changing production ecology of British pre-school television in light of developments since the mid-1990s and the specific role played by the BBC. Underpinning the research is the perception that pre-school television is characterised by a complex set of industry relationships and dependencies that demands content which needs to satisfy a wide range of international circumstances and commercial prerogatives. For the BBC this has created tension between its public service goals and commercial priorities. Pre-school programming began in Britain in 1950, but it was not until the mid-1990s that Britain emerged as a leading producer of pre-school programming worldwide with government/industry reports regularly identifying the children’s production sector as an important contributor to exports. The rise of pre-school niche channels (CBeebies, Nick Junior, Playhouse Disney), audience fragmentation and the internationalisation and commercialisation of markets have radically altered the funding base of children’s television and the relationships that the BBC enjoys with key players. The international success of much of its pre-school programming is based on the relationships it enjoys with independent producers who generate significant revenues from programme-related consumer products. This paper focuses on the complex and changing relationships between the BBC, independent producers, and financiers, that constitute the production ecology of pre-school television and shape its output. Within the broader setting of cultural production and global trends the paper investigates the following questions: 1) In the light of changes to the sector since the mid-1990s, what makes pre-school television significant both generally and as an ideal public service project? 2) What is the nature of the current funding crisis in British children’s television and what implications does this crisis have for the BBC’s involvement in pre-school television? 3) How is the Corporation reacting to and managing the wider commercial, cultural, regulatory and technological forces that are likely to affect its strategies for the commissioning, production and acquisition of pre-school content?

Hollywood and world cinema influences: tracing intertextuality in the works of two contemporary filmmakers from Francophone Africa; Mahamat Saleh Haroun and Abderrahmane Sissako

Don’t tell me the moon is shining; show me the glint of light on broken glass Anton Chekhov Representations of Africa in cinema are almost as old as cinema itself and date back to Hollywood’s silent era. Most early examples feature the continent as a mere exotic backdrop and include The Sheik (Melford 1921), soon followed, in 1926, by George Fitzmaurice’s Son of the Sheik starring Rudolph Valentino. The next decade brought Van Dyke’s Tarzan movies, Robert Stevenson’s King Solomon’s Mines (1937), and, on the European side, Duvivier’s Pépé le Moko (1936). For representations of Francophone Africa by Africans themselves, the viewing public more or less had to wait, however, until decolonisation in the 1960s (with, for example, Sembene Ousmane’s Borom Sarret and La Noire de…, both released in 1966 and, in 1968, Mandabi). Since then Francophone African cinema has come a long way and has diversified into various strands. Between Borom Sarret and Mahamat-Saleh Haroun’s 2006 Daratt, Saison sèche - or the same director’s Un homme qui crie, almost half a century has elapsed. Over this period, films inevitably have addressed a spectrum of visual, ideological and political tropes. They range from unadorned depictions of the newly independent states and their societies to highly aestheticised productions, not to mention surreal and poetic visions as displayed for instance in Djibril Diop Mambéty’s Touki Bouki (1973). Most of the early films send an overt socio-political message which is a clear and explicit denunciation of a corrupt state of affairs (Souleymane Cissé’s Baara, 1977). They aim to trigger strong emotional and political responses from the viewer, in unambiguous support for the film-maker’s stand. Sembene himself declared: “I consider cinema a means of political action” (Murphy 2000: 221). Similarly, the Mauritanian director Med Hondo wishes to “take up this technical medium and to make it a mouthpiece on behalf of [his] fellow Africans and Arabs” (Jeffries 2002: 11). All this echoes the claims of the Fédération Panafricaine des Cinéastes (FEPACI, founded in 1969), an organisation “dedicated to the liberation of Africa”. In sharp contrast to the incipient momentum given Francophonie by Bourguiba, the Nigerien Hamani Diori and the Senegalese Senghor, who invoked a worldwide communauté organique francophone, FEPACI called for “the creation of an aesthetics of disalienation… [using] didactic... forms to denounce the alienation of countries that were politically independent but culturally and economically dependent on the West” (Diawara 1996: 40). Sembene’s Xala (1974) became the blueprint for this, to this day the best-known vein of Francophone African cinema. Thus considered, this pedigree seems a million miles from mainstream global cinema with its overriding mission to entertain. A question therefore arises: to what extent can a cinema that sprang from such beginnings be seen to interface in any meaningful way with a global film industry that, overwhelmingly and for a century, has indeed entertained the world – with Hollywood at its centre?

Patterns of cortisol and DHEA secretion and relationships with attachment style and psychosocial variables in female adolescents: a developmental psychopathology approach

This programme of research used a developmental psychopathology approach to investigate females across the adolescent period. A two-sided story is presented; first, a study of neuroendocrine and psychosocial parameters in a group of healthy female adolescents (N = 63), followed by a parallel study of female adolescents with anorexia nervosa (AN) (N = 8). A biopsychosocial, multi-method measurement approach was taken, which utilised self-report, interview and hypothalamic-pituitary-adrenocortical (HPA) axis measures. Saliva samples for the measurement of cortisol and DHEA were collected using the best-recommended methodology: multiple samples over the day, strict reference to time of awakening, and two consecutive sampling weekdays. The research was adolescent-orientated: specifically, by using creative and ageappropriate strategies to ensure participant adherence to protocol, as well as more generally by adopting various procedures to facilitate engagement with the research process. In the healthy females mean (± SD) age 13.9 (± 2.7) years, cortisol and DHEA secretion exhibited typical adult-like diurnal patterns. Developmental markers of chronological age, menarche status and body mass index (BMI) had differential associations with cortisol and DHEA secretory activity. The pattern of the cortisol awakening response (CAR) was sensitive to whether participants had experienced first menses, but not to chronological age or BMI. Those who were post-menarche generally reached their peak point of cortisol secretion at 45 minutes post-awakening, in contrast to the pre-menarche group who were more evenly spread. Subsequent daytime cortisol levels were also higher in post-menarche females, and this effect was also noted for increasing age and BMI. Both morning and evening DHEA were positively associated with developmental markers. None of the situational or self-report psychosocial variables that were measured modulated any of the key findings regarding cortisol and DHEA secretion. The healthy group of girls were within age-appropriate norms for all the self-report measures used, however just under half of this group were insecurely attached (as assessed by interview). Only attachment style was associated with neuroendocrine parameters. In particular, those with an anxious insecure style exhibited a higher awakening sample (levels were 7.16 nmol/l, 10.40 nmol/l and 7.93 nmol/l for secure, anxious and avoidant groups, respectively) and a flatter CAR (mean increases over the awakening period were 6.38 nmol/l, 2.32 nmol/l and 8.61 nmol/l for secure, anxious and avoidant groups, respectively). The afore-mentioned pattern is similar to that consistently associated with psychological disorder in adults, and so this may be a pre-clinical vulnerability factor for subsequent mental health problems. A group of females with AN, mean (± SD) age 15.1 (± 1.6) years, were recruited from a specialist residential clinic and compared to the above group of healthy control (HC) female adolescents. A general picture of cortisol and DHEA hypersecretion was revealed in those with AN. The mean (± SD) change exhibited in cortisol levels over the 30 minute post-awakening period was 7.05 nmol/l (± 5.99) and 8.33 nmol/l (± 6.41) for HC and AN groups, respectively. The mean (± SD) evening cortisol level for the HC girls was 1.95 nmol/l (± 2.11), in comparison to 6.42 nmol/l (± 11.10) for the AN group. Mean (± SD) morning DHEA concentrations were 1.47 nmol/l (± 0.85) and 2.25 nmol/l (± 0.88) for HC and AN groups, respectively. The HC group’s mean (± SD) concentration of 12 hour DHEA was 0.55 nmol/l (± 0.46) and the AN group’s mean level was 0.89 nmol/l (± 0.90). This adrenal steroid hypersecretion evidenced by the AN group was not associated with BMI or eating disorder symptomatology. Insecure attachment characterised by fearfulness and anger was most apparent; a style which was unparalleled in the healthy group of female adolescents. The causal directions of the AN group findings remain unclear. Examining some of the participants with AN as case studies one year post-discharge from the clinic illustrated that for one participant who was recovered, in terms of returning to ordinary school life and no longer exhibiting clinical levels of eating disorder symptomatology, her CARs were no longer inconsistent over sampling days and her DHEA levels were also now generally comparable to the healthy control group. For another participant who had not recovered from her AN one year later, the profile of her CAR continued to be inconsistent over sampling days and her DHEA concentrations over the diurnal period were significantly higher in comparison to the healthy control group. In its entirety, this work’s unique contribution lies in its consideration of methodological and developmental issues specifically pertaining to adolescents. Findings also contribute to knowledge of AN and understanding of vulnerability factors, and how these may be used to develop interventions dedicated to improving adolescent health.